Jul 5, 2011
NASA -- Images courtesy of Tad Pfeffer, Institute of Arctic and Alpine Research, University of Colorado. Detailed image credits: 1) Columbia Glacier c. 1980 by Austin Post, U.S. Geological Survey, 2) Columbia Glacier 2005 by Tad Pfeffer, Institute of Arctic and Alpine Research, University of Colorado, 3) Arapaho Glacier 1898 by R.S. Brackett, published in Waldrop, R.S. (1964) Arapaho Glacier: A Sixty Year Record. University of Colorado Studies, Series in Geology, No 3, and 4) Arapaho Glacier 2003 by Tad Pfeffer.